Prior art methods by which a radio frequency tube such as a traveling wave tube (TWT) may be powered and modulated include high voltage battery prime power operation and low voltage battery prime power operation. High voltage battery operation of a TWT continuous wave (CW) over the entire period of operation can be accomplished with a high voltage battery having a self-contained activation system. The TWT filament power is derived from a suitably designed section integral to the negative end cells of the high voltage unit. A pulse loaded battery the same size as the CW battery can be used, the peak and CW currents being equal. Critical factors effecting the feasibility of the CW approach are the development of a reliable high voltage battery and the development of a TWT which can sustain CW operation at high power. A high voltage battery prime power source with a form of modulation such as cathode modulation requires high voltage switches capable of handling full cathode voltage and feed current. Where the system is to operate under shock and vibration environment, there appears to be no suitable relay that can maintain operation. A high voltage string of silicon control rectifiers or transistors is feasible for maintaining operation, with sufficient compensation to prevent failure, but these have not been completely successful in prior art operation. A line type pulser can be employed using a cathode pulse modulator with a low voltage solid state pulse generation and a separate transformer to obtain high voltage. However, with the line type pulser using the pulse transformer, it is impossible to obtain both rise time and ripple on top of the pulse simultaneously. The current waveform requirement is more difficult to meet with a line type pulser. It is possible to design the discharge characteristics of the pulse forming network to give the leading edge spike and flat portion of the waveform but it is not possible to obtain the negative spike on the trailing edge of the waveform which allows a fast fall time to be obtained.
Voltage pulsers for radio frequency tubes are well established in the prior art. Typically "Introduction to Radar Systems" by M. I. Sknolnik, McGraw-Hill Book Company, 1962, pages 248-254 disclose pulsers. Similarly, the "Radar Handbook" by M. I. Sknolnik, McGraw-Hill Book Company, 1970, pages 7-68 through 7-87 disclose considerable background in radio frequency tube modulator circuits.